diff --git a/src/addrman.cpp b/src/addrman.cpp
index 11dd2a7b..345261e2 100644
--- a/src/addrman.cpp
+++ b/src/addrman.cpp
@@ -8,12 +8,12 @@ using namespace std;
 
 int CAddrInfo::GetTriedBucket(const std::vector<unsigned char> &nKey) const
 {
-    CDataStream ss1(SER_GETHASH);
+    CDataStream ss1(SER_GETHASH, 0);
     std::vector<unsigned char> vchKey = GetKey();
     ss1 << nKey << vchKey;
     uint64 hash1 = Hash(ss1.begin(), ss1.end()).Get64();
 
-    CDataStream ss2(SER_GETHASH);
+    CDataStream ss2(SER_GETHASH, 0);
     std::vector<unsigned char> vchGroupKey = GetGroup();
     ss2 << nKey << vchGroupKey << (hash1 % ADDRMAN_TRIED_BUCKETS_PER_GROUP);
     uint64 hash2 = Hash(ss2.begin(), ss2.end()).Get64();
@@ -22,13 +22,13 @@ int CAddrInfo::GetTriedBucket(const std::vector<unsigned char> &nKey) const
 
 int CAddrInfo::GetNewBucket(const std::vector<unsigned char> &nKey, const CNetAddr& src) const
 {
-    CDataStream ss1(SER_GETHASH);
+    CDataStream ss1(SER_GETHASH, 0);
     std::vector<unsigned char> vchGroupKey = GetGroup();
     std::vector<unsigned char> vchSourceGroupKey = src.GetGroup();
     ss1 << nKey << vchGroupKey << vchSourceGroupKey;
     uint64 hash1 = Hash(ss1.begin(), ss1.end()).Get64();
 
-    CDataStream ss2(SER_GETHASH);
+    CDataStream ss2(SER_GETHASH, 0);
     ss2 << nKey << vchSourceGroupKey << (hash1 % ADDRMAN_NEW_BUCKETS_PER_SOURCE_GROUP);
     uint64 hash2 = Hash(ss2.begin(), ss2.end()).Get64();
     return hash2 % ADDRMAN_NEW_BUCKET_COUNT;
diff --git a/src/base58.h b/src/base58.h
index 24b7f3ab..90ce34b0 100644
--- a/src/base58.h
+++ b/src/base58.h
@@ -19,7 +19,6 @@
 #include <vector>
 #include "bignum.h"
 #include "key.h"
-#include "util.h"
 
 static const char* pszBase58 = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";
 
diff --git a/src/bitcoinrpc.cpp b/src/bitcoinrpc.cpp
index e201bbe6..b7d00c40 100644
--- a/src/bitcoinrpc.cpp
+++ b/src/bitcoinrpc.cpp
@@ -142,7 +142,7 @@ Object blockToJSON(const CBlock& block, const CBlockIndex* blockindex)
 {
     Object result;
     result.push_back(Pair("hash", block.GetHash().GetHex()));
-    result.push_back(Pair("size", (int)::GetSerializeSize(block, SER_NETWORK)));
+    result.push_back(Pair("size", (int)::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION)));
     result.push_back(Pair("height", blockindex->nHeight));
     result.push_back(Pair("version", block.nVersion));
     result.push_back(Pair("merkleroot", block.hashMerkleRoot.GetHex()));
@@ -602,7 +602,7 @@ Value signmessage(const Array& params, bool fHelp)
     if (!pwalletMain->GetKey(addr, key))
         throw JSONRPCError(-4, "Private key not available");
 
-    CDataStream ss(SER_GETHASH);
+    CDataStream ss(SER_GETHASH, 0);
     ss << strMessageMagic;
     ss << strMessage;
 
@@ -634,7 +634,7 @@ Value verifymessage(const Array& params, bool fHelp)
     if (fInvalid)
         throw JSONRPCError(-5, "Malformed base64 encoding");
 
-    CDataStream ss(SER_GETHASH);
+    CDataStream ss(SER_GETHASH, 0);
     ss << strMessageMagic;
     ss << strMessage;
 
@@ -1921,7 +1921,7 @@ Value getmemorypool(const Array& params, bool fHelp)
             if(tx.IsCoinBase())
                 continue;
 
-            CDataStream ssTx;
+            CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
             ssTx << tx;
 
             transactions.push_back(HexStr(ssTx.begin(), ssTx.end()));
@@ -1943,7 +1943,7 @@ Value getmemorypool(const Array& params, bool fHelp)
     else
     {
         // Parse parameters
-        CDataStream ssBlock(ParseHex(params[0].get_str()));
+        CDataStream ssBlock(ParseHex(params[0].get_str()), SER_NETWORK, PROTOCOL_VERSION);
         CBlock pblock;
         ssBlock >> pblock;
 
diff --git a/src/crypter.cpp b/src/crypter.cpp
index 5713faf1..4f37575a 100644
--- a/src/crypter.cpp
+++ b/src/crypter.cpp
@@ -11,7 +11,6 @@
 #endif
 
 #include "crypter.h"
-#include "util.h"
 
 bool CCrypter::SetKeyFromPassphrase(const SecureString& strKeyData, const std::vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod)
 {
diff --git a/src/crypter.h b/src/crypter.h
index 59a005a2..d1bdb92c 100644
--- a/src/crypter.h
+++ b/src/crypter.h
@@ -6,6 +6,7 @@
 
 #include "allocators.h" /* for SecureString */
 #include "key.h"
+#include "serialize.h"
 
 const unsigned int WALLET_CRYPTO_KEY_SIZE = 32;
 const unsigned int WALLET_CRYPTO_SALT_SIZE = 8;
diff --git a/src/db.cpp b/src/db.cpp
index 447759f3..c67cf2f8 100644
--- a/src/db.cpp
+++ b/src/db.cpp
@@ -6,7 +6,6 @@
 #include "db.h"
 #include "util.h"
 #include "main.h"
-#include "wallet.h"
 #include <boost/version.hpp>
 #include <boost/filesystem.hpp>
 #include <boost/filesystem/fstream.hpp>
@@ -229,8 +228,8 @@ bool CDB::Rewrite(const string& strFile, const char* pszSkip)
                     if (pcursor)
                         while (fSuccess)
                         {
-                            CDataStream ssKey;
-                            CDataStream ssValue;
+                            CDataStream ssKey(SER_DISK, CLIENT_VERSION);
+                            CDataStream ssValue(SER_DISK, CLIENT_VERSION);
                             int ret = db.ReadAtCursor(pcursor, ssKey, ssValue, DB_NEXT);
                             if (ret == DB_NOTFOUND)
                             {
@@ -386,10 +385,10 @@ bool CTxDB::ReadOwnerTxes(uint160 hash160, int nMinHeight, vector<CTransaction>&
     loop
     {
         // Read next record
-        CDataStream ssKey;
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         if (fFlags == DB_SET_RANGE)
             ssKey << string("owner") << hash160 << CDiskTxPos(0, 0, 0);
-        CDataStream ssValue;
+        CDataStream ssValue(SER_DISK, CLIENT_VERSION);
         int ret = ReadAtCursor(pcursor, ssKey, ssValue, fFlags);
         fFlags = DB_NEXT;
         if (ret == DB_NOTFOUND)
@@ -514,10 +513,10 @@ bool CTxDB::LoadBlockIndex()
     loop
     {
         // Read next record
-        CDataStream ssKey;
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         if (fFlags == DB_SET_RANGE)
             ssKey << make_pair(string("blockindex"), uint256(0));
-        CDataStream ssValue;
+        CDataStream ssValue(SER_DISK, CLIENT_VERSION);
         int ret = ReadAtCursor(pcursor, ssKey, ssValue, fFlags);
         fFlags = DB_NEXT;
         if (ret == DB_NOTFOUND)
@@ -754,8 +753,8 @@ bool CAddrDB::LoadAddresses()
     loop
     {
         // Read next record
-        CDataStream ssKey;
-        CDataStream ssValue;
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
+        CDataStream ssValue(SER_DISK, CLIENT_VERSION);
         int ret = ReadAtCursor(pcursor, ssKey, ssValue);
         if (ret == DB_NOTFOUND)
             break;
diff --git a/src/db.h b/src/db.h
index 1cd16259..48e10a95 100644
--- a/src/db.h
+++ b/src/db.h
@@ -5,7 +5,6 @@
 #ifndef BITCOIN_DB_H
 #define BITCOIN_DB_H
 
-#include "key.h"
 #include "main.h"
 
 #include <map>
@@ -58,7 +57,7 @@ protected:
             return false;
 
         // Key
-        CDataStream ssKey(SER_DISK);
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         ssKey.reserve(1000);
         ssKey << key;
         Dbt datKey(&ssKey[0], ssKey.size());
@@ -72,7 +71,7 @@ protected:
             return false;
 
         // Unserialize value
-        CDataStream ssValue((char*)datValue.get_data(), (char*)datValue.get_data() + datValue.get_size(), SER_DISK);
+        CDataStream ssValue((char*)datValue.get_data(), (char*)datValue.get_data() + datValue.get_size(), SER_DISK, CLIENT_VERSION);
         ssValue >> value;
 
         // Clear and free memory
@@ -90,13 +89,13 @@ protected:
             assert(!"Write called on database in read-only mode");
 
         // Key
-        CDataStream ssKey(SER_DISK);
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         ssKey.reserve(1000);
         ssKey << key;
         Dbt datKey(&ssKey[0], ssKey.size());
 
         // Value
-        CDataStream ssValue(SER_DISK);
+        CDataStream ssValue(SER_DISK, CLIENT_VERSION);
         ssValue.reserve(10000);
         ssValue << value;
         Dbt datValue(&ssValue[0], ssValue.size());
@@ -119,7 +118,7 @@ protected:
             assert(!"Erase called on database in read-only mode");
 
         // Key
-        CDataStream ssKey(SER_DISK);
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         ssKey.reserve(1000);
         ssKey << key;
         Dbt datKey(&ssKey[0], ssKey.size());
@@ -139,7 +138,7 @@ protected:
             return false;
 
         // Key
-        CDataStream ssKey(SER_DISK);
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         ssKey.reserve(1000);
         ssKey << key;
         Dbt datKey(&ssKey[0], ssKey.size());
diff --git a/src/init.cpp b/src/init.cpp
index 886b3ab6..0eb37fe9 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -7,7 +7,6 @@
 #include "bitcoinrpc.h"
 #include "net.h"
 #include "init.h"
-#include "strlcpy.h"
 #include "util.h"
 #include "ui_interface.h"
 #include <boost/filesystem.hpp>
diff --git a/src/key.h b/src/key.h
index 8f220f1c..fc113182 100644
--- a/src/key.h
+++ b/src/key.h
@@ -12,7 +12,7 @@
 #include <openssl/ecdsa.h>
 #include <openssl/obj_mac.h>
 
-#include "serialize.h"
+// #include "serialize.h"
 #include "uint256.h"
 
 // secp160k1
diff --git a/src/keystore.cpp b/src/keystore.cpp
index 664f0b12..31351871 100644
--- a/src/keystore.cpp
+++ b/src/keystore.cpp
@@ -4,7 +4,6 @@
 // file license.txt or http://www.opensource.org/licenses/mit-license.php.
 
 #include "keystore.h"
-#include "crypter.h"
 #include "script.h"
 
 bool CKeyStore::GetPubKey(const CBitcoinAddress &address, std::vector<unsigned char> &vchPubKeyOut) const
diff --git a/src/keystore.h b/src/keystore.h
index 5d29ac1c..76820e20 100644
--- a/src/keystore.h
+++ b/src/keystore.h
@@ -6,7 +6,10 @@
 #define BITCOIN_KEYSTORE_H
 
 #include "crypter.h"
-#include "script.h"
+#include "util.h"
+#include "base58.h"
+
+class CScript;
 
 /** A virtual base class for key stores */
 class CKeyStore
diff --git a/src/main.cpp b/src/main.cpp
index c2236d99..16a1f345 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -411,7 +411,7 @@ bool CTransaction::CheckTransaction() const
     if (vout.empty())
         return DoS(10, error("CTransaction::CheckTransaction() : vout empty"));
     // Size limits
-    if (::GetSerializeSize(*this, SER_NETWORK) > MAX_BLOCK_SIZE)
+    if (::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION) > MAX_BLOCK_SIZE)
         return DoS(100, error("CTransaction::CheckTransaction() : size limits failed"));
 
     // Check for negative or overflow output values
@@ -533,7 +533,7 @@ bool CTransaction::AcceptToMemoryPool(CTxDB& txdb, bool fCheckInputs, bool* pfMi
         // reasonable number of ECDSA signature verifications.
 
         int64 nFees = GetValueIn(mapInputs)-GetValueOut();
-        unsigned int nSize = ::GetSerializeSize(*this, SER_NETWORK);
+        unsigned int nSize = ::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION);
 
         // Don't accept it if it can't get into a block
         if (nFees < GetMinFee(1000, true, GMF_RELAY))
@@ -1279,7 +1279,7 @@ bool CBlock::ConnectBlock(CTxDB& txdb, CBlockIndex* pindex)
     bool fStrictPayToScriptHash = (pindex->nTime >= nBIP16SwitchTime);
 
     //// issue here: it doesn't know the version
-    unsigned int nTxPos = pindex->nBlockPos + ::GetSerializeSize(CBlock(), SER_DISK) - 1 + GetSizeOfCompactSize(vtx.size());
+    unsigned int nTxPos = pindex->nBlockPos + ::GetSerializeSize(CBlock(), SER_DISK, CLIENT_VERSION) - 1 + GetSizeOfCompactSize(vtx.size());
 
     map<uint256, CTxIndex> mapQueuedChanges;
     int64 nFees = 0;
@@ -1291,7 +1291,7 @@ bool CBlock::ConnectBlock(CTxDB& txdb, CBlockIndex* pindex)
             return DoS(100, error("ConnectBlock() : too many sigops"));
 
         CDiskTxPos posThisTx(pindex->nFile, pindex->nBlockPos, nTxPos);
-        nTxPos += ::GetSerializeSize(tx, SER_DISK);
+        nTxPos += ::GetSerializeSize(tx, SER_DISK, CLIENT_VERSION);
 
         MapPrevTx mapInputs;
         if (!tx.IsCoinBase())
@@ -1621,7 +1621,7 @@ bool CBlock::CheckBlock() const
     // that can be verified before saving an orphan block.
 
     // Size limits
-    if (vtx.empty() || vtx.size() > MAX_BLOCK_SIZE || ::GetSerializeSize(*this, SER_NETWORK) > MAX_BLOCK_SIZE)
+    if (vtx.empty() || vtx.size() > MAX_BLOCK_SIZE || ::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION) > MAX_BLOCK_SIZE)
         return DoS(100, error("CheckBlock() : size limits failed"));
 
     // Check proof of work matches claimed amount
@@ -1691,7 +1691,7 @@ bool CBlock::AcceptBlock()
         return DoS(100, error("AcceptBlock() : rejected by checkpoint lockin at %d", nHeight));
 
     // Write block to history file
-    if (!CheckDiskSpace(::GetSerializeSize(*this, SER_DISK)))
+    if (!CheckDiskSpace(::GetSerializeSize(*this, SER_DISK, CLIENT_VERSION)))
         return error("AcceptBlock() : out of disk space");
     unsigned int nFile = -1;
     unsigned int nBlockPos = 0;
@@ -2481,7 +2481,7 @@ bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
             pfrom->PushInventory(CInv(MSG_BLOCK, pindex->GetBlockHash()));
             CBlock block;
             block.ReadFromDisk(pindex, true);
-            nBytes += block.GetSerializeSize(SER_NETWORK);
+            nBytes += block.GetSerializeSize(SER_NETWORK, PROTOCOL_VERSION);
             if (--nLimit <= 0 || nBytes >= SendBufferSize()/2)
             {
                 // When this block is requested, we'll send an inv that'll make them
@@ -3174,7 +3174,7 @@ CBlock* CreateNewBlock(CReserveKey& reservekey)
             }
 
             // Priority is sum(valuein * age) / txsize
-            dPriority /= ::GetSerializeSize(tx, SER_NETWORK);
+            dPriority /= ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
 
             if (porphan)
                 porphan->dPriority = dPriority;
@@ -3203,7 +3203,7 @@ CBlock* CreateNewBlock(CReserveKey& reservekey)
             mapPriority.erase(mapPriority.begin());
 
             // Size limits
-            unsigned int nTxSize = ::GetSerializeSize(tx, SER_NETWORK);
+            unsigned int nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
             if (nBlockSize + nTxSize >= MAX_BLOCK_SIZE_GEN)
                 continue;
 
diff --git a/src/main.h b/src/main.h
index b6bce014..bcd62080 100644
--- a/src/main.h
+++ b/src/main.h
@@ -7,9 +7,7 @@
 
 #include "bignum.h"
 #include "net.h"
-#include "key.h"
 #include "script.h"
-#include "version.h"
 
 #ifdef WIN32
 #include <io.h> /* for _commit */
@@ -545,7 +543,7 @@ public:
         // Base fee is either MIN_TX_FEE or MIN_RELAY_TX_FEE
         int64 nBaseFee = (mode == GMF_RELAY) ? MIN_RELAY_TX_FEE : MIN_TX_FEE;
 
-        unsigned int nBytes = ::GetSerializeSize(*this, SER_NETWORK);
+        unsigned int nBytes = ::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION);
         unsigned int nNewBlockSize = nBlockSize + nBytes;
         int64 nMinFee = (1 + (int64)nBytes / 1000) * nBaseFee;
 
@@ -590,7 +588,7 @@ public:
 
     bool ReadFromDisk(CDiskTxPos pos, FILE** pfileRet=NULL)
     {
-        CAutoFile filein = OpenBlockFile(pos.nFile, 0, pfileRet ? "rb+" : "rb");
+        CAutoFile filein = CAutoFile(OpenBlockFile(pos.nFile, 0, pfileRet ? "rb+" : "rb"), SER_DISK, CLIENT_VERSION);
         if (!filein)
             return error("CTransaction::ReadFromDisk() : OpenBlockFile failed");
 
@@ -941,7 +939,7 @@ public:
     bool WriteToDisk(unsigned int& nFileRet, unsigned int& nBlockPosRet)
     {
         // Open history file to append
-        CAutoFile fileout = AppendBlockFile(nFileRet);
+        CAutoFile fileout = CAutoFile(AppendBlockFile(nFileRet), SER_DISK, CLIENT_VERSION);
         if (!fileout)
             return error("CBlock::WriteToDisk() : AppendBlockFile failed");
 
@@ -974,7 +972,7 @@ public:
         SetNull();
 
         // Open history file to read
-        CAutoFile filein = OpenBlockFile(nFile, nBlockPos, "rb");
+        CAutoFile filein = CAutoFile(OpenBlockFile(nFile, nBlockPos, "rb"), SER_DISK, CLIENT_VERSION);
         if (!filein)
             return error("CBlock::ReadFromDisk() : OpenBlockFile failed");
         if (!fReadTransactions)
@@ -1135,7 +1133,7 @@ public:
     bool EraseBlockFromDisk()
     {
         // Open history file
-        CAutoFile fileout = OpenBlockFile(nFile, nBlockPos, "rb+");
+        CAutoFile fileout = CAutoFile(OpenBlockFile(nFile, nBlockPos, "rb+"), SER_DISK, CLIENT_VERSION);
         if (!fileout)
             return false;
 
@@ -1595,7 +1593,7 @@ public:
             return error("CAlert::CheckSignature() : verify signature failed");
 
         // Now unserialize the data
-        CDataStream sMsg(vchMsg);
+        CDataStream sMsg(vchMsg, SER_NETWORK, PROTOCOL_VERSION);
         sMsg >> *(CUnsignedAlert*)this;
         return true;
     }
diff --git a/src/net.h b/src/net.h
index 95bda9ca..bad49a9f 100644
--- a/src/net.h
+++ b/src/net.h
@@ -157,14 +157,10 @@ public:
     CCriticalSection cs_inventory;
     std::multimap<int64, CInv> mapAskFor;
 
-    CNode(SOCKET hSocketIn, CAddress addrIn, bool fInboundIn=false)
+    CNode(SOCKET hSocketIn, CAddress addrIn, bool fInboundIn=false) : vSend(SER_NETWORK, MIN_PROTO_VERSION), vRecv(SER_NETWORK, MIN_PROTO_VERSION)
     {
         nServices = 0;
         hSocket = hSocketIn;
-        vSend.SetType(SER_NETWORK);
-        vRecv.SetType(SER_NETWORK);
-        vSend.SetVersion(MIN_PROTO_VERSION);
-        vRecv.SetVersion(MIN_PROTO_VERSION);
         nLastSend = 0;
         nLastRecv = 0;
         nLastSendEmpty = GetTime();
@@ -612,7 +608,7 @@ inline void RelayInventory(const CInv& inv)
 template<typename T>
 void RelayMessage(const CInv& inv, const T& a)
 {
-    CDataStream ss(SER_NETWORK);
+    CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
     ss.reserve(10000);
     ss << a;
     RelayMessage(inv, ss);
@@ -631,7 +627,7 @@ inline void RelayMessage<>(const CInv& inv, const CDataStream& ss)
         }
 
         // Save original serialized message so newer versions are preserved
-        mapRelay[inv] = ss;
+        mapRelay.insert(std::make_pair(inv, ss));
         vRelayExpiration.push_back(std::make_pair(GetTime() + 15 * 60, inv));
     }
 
diff --git a/src/qt/bitcoin.cpp b/src/qt/bitcoin.cpp
index dfcd2af3..c7830871 100644
--- a/src/qt/bitcoin.cpp
+++ b/src/qt/bitcoin.cpp
@@ -8,6 +8,7 @@
 #include "guiutil.h"
 
 #include "init.h"
+#include "ui_interface.h"
 #include "qtipcserver.h"
 
 #include <QApplication>
diff --git a/src/qt/messagepage.cpp b/src/qt/messagepage.cpp
index 46a0cbae..18bb64fe 100644
--- a/src/qt/messagepage.cpp
+++ b/src/qt/messagepage.cpp
@@ -91,7 +91,7 @@ void MessagePage::on_signMessage_clicked()
         return;
     }
 
-    CDataStream ss(SER_GETHASH);
+    CDataStream ss(SER_GETHASH, 0);
     ss << strMessageMagic;
     ss << ui->message->document()->toPlainText().toStdString();
 
diff --git a/src/qt/qtipcserver.cpp b/src/qt/qtipcserver.cpp
index f7bccaaf..102ac0ff 100644
--- a/src/qt/qtipcserver.cpp
+++ b/src/qt/qtipcserver.cpp
@@ -7,6 +7,7 @@
 #include <boost/tokenizer.hpp>
 #include <boost/date_time/posix_time/posix_time.hpp>
 
+#include "ui_interface.h"
 #include "util.h"
 #include "qtipcserver.h"
 
diff --git a/src/qt/walletmodel.cpp b/src/qt/walletmodel.cpp
index e23a2bb0..7a83f6ce 100644
--- a/src/qt/walletmodel.cpp
+++ b/src/qt/walletmodel.cpp
@@ -4,6 +4,7 @@
 #include "addresstablemodel.h"
 #include "transactiontablemodel.h"
 
+#include "ui_interface.h"
 #include "wallet.h"
 #include "walletdb.h" // for BackupWallet
 
diff --git a/src/script.cpp b/src/script.cpp
index ac1f0405..fc0a5b3e 100644
--- a/src/script.cpp
+++ b/src/script.cpp
@@ -1092,7 +1092,7 @@ uint256 SignatureHash(CScript scriptCode, const CTransaction& txTo, unsigned int
     }
 
     // Serialize and hash
-    CDataStream ss(SER_GETHASH);
+    CDataStream ss(SER_GETHASH, 0);
     ss.reserve(10000);
     ss << txTmp << nHashType;
     return Hash(ss.begin(), ss.end());
diff --git a/src/serialize.h b/src/serialize.h
index 89f498e7..12ea1ec6 100644
--- a/src/serialize.h
+++ b/src/serialize.h
@@ -57,7 +57,7 @@ enum
 };
 
 #define IMPLEMENT_SERIALIZE(statements)    \
-    unsigned int GetSerializeSize(int nType=0, int nVersion=PROTOCOL_VERSION) const  \
+    unsigned int GetSerializeSize(int nType, int nVersion) const  \
     {                                           \
         CSerActionGetSerializeSize ser_action;  \
         const bool fGetSize = true;             \
@@ -72,7 +72,7 @@ enum
         return nSerSize;                        \
     }                                           \
     template<typename Stream>                   \
-    void Serialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION) const  \
+    void Serialize(Stream& s, int nType, int nVersion) const  \
     {                                           \
         CSerActionSerialize ser_action;         \
         const bool fGetSize = false;            \
@@ -83,7 +83,7 @@ enum
         {statements}                            \
     }                                           \
     template<typename Stream>                   \
-    void Unserialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION)  \
+    void Unserialize(Stream& s, int nType, int nVersion)  \
     {                                           \
         CSerActionUnserialize ser_action;       \
         const bool fGetSize = false;            \
@@ -287,43 +287,43 @@ template<typename Stream, typename C> void Unserialize(Stream& is, std::basic_st
 // vector
 template<typename T, typename A> unsigned int GetSerializeSize_impl(const std::vector<T, A>& v, int nType, int nVersion, const boost::true_type&);
 template<typename T, typename A> unsigned int GetSerializeSize_impl(const std::vector<T, A>& v, int nType, int nVersion, const boost::false_type&);
-template<typename T, typename A> inline unsigned int GetSerializeSize(const std::vector<T, A>& v, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename T, typename A> inline unsigned int GetSerializeSize(const std::vector<T, A>& v, int nType, int nVersion);
 template<typename Stream, typename T, typename A> void Serialize_impl(Stream& os, const std::vector<T, A>& v, int nType, int nVersion, const boost::true_type&);
 template<typename Stream, typename T, typename A> void Serialize_impl(Stream& os, const std::vector<T, A>& v, int nType, int nVersion, const boost::false_type&);
-template<typename Stream, typename T, typename A> inline void Serialize(Stream& os, const std::vector<T, A>& v, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename Stream, typename T, typename A> inline void Serialize(Stream& os, const std::vector<T, A>& v, int nType, int nVersion);
 template<typename Stream, typename T, typename A> void Unserialize_impl(Stream& is, std::vector<T, A>& v, int nType, int nVersion, const boost::true_type&);
 template<typename Stream, typename T, typename A> void Unserialize_impl(Stream& is, std::vector<T, A>& v, int nType, int nVersion, const boost::false_type&);
-template<typename Stream, typename T, typename A> inline void Unserialize(Stream& is, std::vector<T, A>& v, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename Stream, typename T, typename A> inline void Unserialize(Stream& is, std::vector<T, A>& v, int nType, int nVersion);
 
 // others derived from vector
-extern inline unsigned int GetSerializeSize(const CScript& v, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream> void Serialize(Stream& os, const CScript& v, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream> void Unserialize(Stream& is, CScript& v, int nType, int nVersion=PROTOCOL_VERSION);
+extern inline unsigned int GetSerializeSize(const CScript& v, int nType, int nVersion);
+template<typename Stream> void Serialize(Stream& os, const CScript& v, int nType, int nVersion);
+template<typename Stream> void Unserialize(Stream& is, CScript& v, int nType, int nVersion);
 
 // pair
-template<typename K, typename T> unsigned int GetSerializeSize(const std::pair<K, T>& item, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename K, typename T> void Serialize(Stream& os, const std::pair<K, T>& item, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename K, typename T> void Unserialize(Stream& is, std::pair<K, T>& item, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename K, typename T> unsigned int GetSerializeSize(const std::pair<K, T>& item, int nType, int nVersion);
+template<typename Stream, typename K, typename T> void Serialize(Stream& os, const std::pair<K, T>& item, int nType, int nVersion);
+template<typename Stream, typename K, typename T> void Unserialize(Stream& is, std::pair<K, T>& item, int nType, int nVersion);
 
 // 3 tuple
-template<typename T0, typename T1, typename T2> unsigned int GetSerializeSize(const boost::tuple<T0, T1, T2>& item, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename T0, typename T1, typename T2> void Serialize(Stream& os, const boost::tuple<T0, T1, T2>& item, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename T0, typename T1, typename T2> void Unserialize(Stream& is, boost::tuple<T0, T1, T2>& item, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename T0, typename T1, typename T2> unsigned int GetSerializeSize(const boost::tuple<T0, T1, T2>& item, int nType, int nVersion);
+template<typename Stream, typename T0, typename T1, typename T2> void Serialize(Stream& os, const boost::tuple<T0, T1, T2>& item, int nType, int nVersion);
+template<typename Stream, typename T0, typename T1, typename T2> void Unserialize(Stream& is, boost::tuple<T0, T1, T2>& item, int nType, int nVersion);
 
 // 4 tuple
-template<typename T0, typename T1, typename T2, typename T3> unsigned int GetSerializeSize(const boost::tuple<T0, T1, T2, T3>& item, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename T0, typename T1, typename T2, typename T3> void Serialize(Stream& os, const boost::tuple<T0, T1, T2, T3>& item, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename T0, typename T1, typename T2, typename T3> void Unserialize(Stream& is, boost::tuple<T0, T1, T2, T3>& item, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename T0, typename T1, typename T2, typename T3> unsigned int GetSerializeSize(const boost::tuple<T0, T1, T2, T3>& item, int nType, int nVersion);
+template<typename Stream, typename T0, typename T1, typename T2, typename T3> void Serialize(Stream& os, const boost::tuple<T0, T1, T2, T3>& item, int nType, int nVersion);
+template<typename Stream, typename T0, typename T1, typename T2, typename T3> void Unserialize(Stream& is, boost::tuple<T0, T1, T2, T3>& item, int nType, int nVersion);
 
 // map
-template<typename K, typename T, typename Pred, typename A> unsigned int GetSerializeSize(const std::map<K, T, Pred, A>& m, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename K, typename T, typename Pred, typename A> void Serialize(Stream& os, const std::map<K, T, Pred, A>& m, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename K, typename T, typename Pred, typename A> void Unserialize(Stream& is, std::map<K, T, Pred, A>& m, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename K, typename T, typename Pred, typename A> unsigned int GetSerializeSize(const std::map<K, T, Pred, A>& m, int nType, int nVersion);
+template<typename Stream, typename K, typename T, typename Pred, typename A> void Serialize(Stream& os, const std::map<K, T, Pred, A>& m, int nType, int nVersion);
+template<typename Stream, typename K, typename T, typename Pred, typename A> void Unserialize(Stream& is, std::map<K, T, Pred, A>& m, int nType, int nVersion);
 
 // set
-template<typename K, typename Pred, typename A> unsigned int GetSerializeSize(const std::set<K, Pred, A>& m, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename K, typename Pred, typename A> void Serialize(Stream& os, const std::set<K, Pred, A>& m, int nType, int nVersion=PROTOCOL_VERSION);
-template<typename Stream, typename K, typename Pred, typename A> void Unserialize(Stream& is, std::set<K, Pred, A>& m, int nType, int nVersion=PROTOCOL_VERSION);
+template<typename K, typename Pred, typename A> unsigned int GetSerializeSize(const std::set<K, Pred, A>& m, int nType, int nVersion);
+template<typename Stream, typename K, typename Pred, typename A> void Serialize(Stream& os, const std::set<K, Pred, A>& m, int nType, int nVersion);
+template<typename Stream, typename K, typename Pred, typename A> void Unserialize(Stream& is, std::set<K, Pred, A>& m, int nType, int nVersion);
 
 
 
@@ -336,19 +336,19 @@ template<typename Stream, typename K, typename Pred, typename A> void Unserializ
 // Thanks to Boost serialization for this idea.
 //
 template<typename T>
-inline unsigned int GetSerializeSize(const T& a, long nType, int nVersion=PROTOCOL_VERSION)
+inline unsigned int GetSerializeSize(const T& a, long nType, int nVersion)
 {
     return a.GetSerializeSize((int)nType, nVersion);
 }
 
 template<typename Stream, typename T>
-inline void Serialize(Stream& os, const T& a, long nType, int nVersion=PROTOCOL_VERSION)
+inline void Serialize(Stream& os, const T& a, long nType, int nVersion)
 {
     a.Serialize(os, (int)nType, nVersion);
 }
 
 template<typename Stream, typename T>
-inline void Unserialize(Stream& is, T& a, long nType, int nVersion=PROTOCOL_VERSION)
+inline void Unserialize(Stream& is, T& a, long nType, int nVersion)
 {
     a.Unserialize(is, (int)nType, nVersion);
 }
@@ -730,39 +730,39 @@ public:
     typedef vector_type::const_iterator   const_iterator;
     typedef vector_type::reverse_iterator reverse_iterator;
 
-    explicit CDataStream(int nTypeIn=SER_NETWORK, int nVersionIn=PROTOCOL_VERSION)
+    explicit CDataStream(int nTypeIn, int nVersionIn)
     {
         Init(nTypeIn, nVersionIn);
     }
 
-    CDataStream(const_iterator pbegin, const_iterator pend, int nTypeIn=SER_NETWORK, int nVersionIn=PROTOCOL_VERSION) : vch(pbegin, pend)
+    CDataStream(const_iterator pbegin, const_iterator pend, int nTypeIn, int nVersionIn) : vch(pbegin, pend)
     {
         Init(nTypeIn, nVersionIn);
     }
 
 #if !defined(_MSC_VER) || _MSC_VER >= 1300
-    CDataStream(const char* pbegin, const char* pend, int nTypeIn=SER_NETWORK, int nVersionIn=PROTOCOL_VERSION) : vch(pbegin, pend)
+    CDataStream(const char* pbegin, const char* pend, int nTypeIn, int nVersionIn) : vch(pbegin, pend)
     {
         Init(nTypeIn, nVersionIn);
     }
 #endif
 
-    CDataStream(const vector_type& vchIn, int nTypeIn=SER_NETWORK, int nVersionIn=PROTOCOL_VERSION) : vch(vchIn.begin(), vchIn.end())
+    CDataStream(const vector_type& vchIn, int nTypeIn, int nVersionIn) : vch(vchIn.begin(), vchIn.end())
     {
         Init(nTypeIn, nVersionIn);
     }
 
-    CDataStream(const std::vector<char>& vchIn, int nTypeIn=SER_NETWORK, int nVersionIn=PROTOCOL_VERSION) : vch(vchIn.begin(), vchIn.end())
+    CDataStream(const std::vector<char>& vchIn, int nTypeIn, int nVersionIn) : vch(vchIn.begin(), vchIn.end())
     {
         Init(nTypeIn, nVersionIn);
     }
 
-    CDataStream(const std::vector<unsigned char>& vchIn, int nTypeIn=SER_NETWORK, int nVersionIn=PROTOCOL_VERSION) : vch((char*)&vchIn.begin()[0], (char*)&vchIn.end()[0])
+    CDataStream(const std::vector<unsigned char>& vchIn, int nTypeIn, int nVersionIn) : vch((char*)&vchIn.begin()[0], (char*)&vchIn.end()[0])
     {
         Init(nTypeIn, nVersionIn);
     }
 
-    void Init(int nTypeIn=SER_NETWORK, int nVersionIn=PROTOCOL_VERSION)
+    void Init(int nTypeIn, int nVersionIn)
     {
         nReadPos = 0;
         nType = nTypeIn;
@@ -976,7 +976,7 @@ public:
     }
 
     template<typename Stream>
-    void Serialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION) const
+    void Serialize(Stream& s, int nType, int nVersion) const
     {
         // Special case: stream << stream concatenates like stream += stream
         if (!vch.empty())
@@ -1085,7 +1085,7 @@ public:
 
     typedef FILE element_type;
 
-    CAutoFile(FILE* filenew=NULL, int nTypeIn=SER_DISK, int nVersionIn=PROTOCOL_VERSION)
+    CAutoFile(FILE* filenew, int nTypeIn, int nVersionIn)
     {
         file = filenew;
         nType = nTypeIn;
diff --git a/src/uint256.h b/src/uint256.h
index 35245805..bf3c55bc 100644
--- a/src/uint256.h
+++ b/src/uint256.h
@@ -10,8 +10,6 @@
 #include <string>
 #include <vector>
 
-#include "version.h"
-
 typedef long long  int64;
 typedef unsigned long long  uint64;
 
@@ -355,19 +353,22 @@ public:
         return pn[2*n] | (uint64)pn[2*n+1] << 32;
     }
 
-    unsigned int GetSerializeSize(int nType=0, int nVersion=PROTOCOL_VERSION) const
+//    unsigned int GetSerializeSize(int nType=0, int nVersion=PROTOCOL_VERSION) const
+    unsigned int GetSerializeSize(int nType, int nVersion) const
     {
         return sizeof(pn);
     }
 
     template<typename Stream>
-    void Serialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION) const
+//    void Serialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION) const
+    void Serialize(Stream& s, int nType, int nVersion) const
     {
         s.write((char*)pn, sizeof(pn));
     }
 
     template<typename Stream>
-    void Unserialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION)
+//    void Unserialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION)
+    void Unserialize(Stream& s, int nType, int nVersion)
     {
         s.read((char*)pn, sizeof(pn));
     }
diff --git a/src/util.cpp b/src/util.cpp
index 19005fc7..ac65d417 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -6,6 +6,7 @@
 #include "util.h"
 #include "strlcpy.h"
 #include "version.h"
+#include "ui_interface.h"
 #include <boost/algorithm/string/join.hpp>
 
 // Work around clang compilation problem in Boost 1.46:
diff --git a/src/util.h b/src/util.h
index a4424771..d9ec68c6 100644
--- a/src/util.h
+++ b/src/util.h
@@ -32,7 +32,6 @@ typedef int pid_t; /* define for windows compatiblity */
 #include <openssl/ripemd.h>
 
 #include "netbase.h" // for AddTimeData
-#include "ui_interface.h"
 
 typedef long long  int64;
 typedef unsigned long long  uint64;
diff --git a/src/wallet.cpp b/src/wallet.cpp
index f8338b78..53836be0 100644
--- a/src/wallet.cpp
+++ b/src/wallet.cpp
@@ -6,6 +6,7 @@
 #include "wallet.h"
 #include "walletdb.h"
 #include "crypter.h"
+#include "ui_interface.h"
 
 using namespace std;
 
@@ -1121,7 +1122,7 @@ bool CWallet::CreateTransaction(const vector<pair<CScript, int64> >& vecSend, CW
                         return false;
 
                 // Limit size
-                unsigned int nBytes = ::GetSerializeSize(*(CTransaction*)&wtxNew, SER_NETWORK);
+                unsigned int nBytes = ::GetSerializeSize(*(CTransaction*)&wtxNew, SER_NETWORK, PROTOCOL_VERSION);
                 if (nBytes >= MAX_BLOCK_SIZE_GEN/5)
                     return false;
                 dPriority /= nBytes;
diff --git a/src/wallet.h b/src/wallet.h
index 3d9387ff..c1461b1f 100644
--- a/src/wallet.h
+++ b/src/wallet.h
@@ -6,7 +6,6 @@
 #define BITCOIN_WALLET_H
 
 #include "main.h"
-#include "bignum.h"
 #include "key.h"
 #include "keystore.h"
 #include "script.h"
diff --git a/src/walletdb.cpp b/src/walletdb.cpp
index dd8069a5..709ecac1 100644
--- a/src/walletdb.cpp
+++ b/src/walletdb.cpp
@@ -74,10 +74,10 @@ void CWalletDB::ListAccountCreditDebit(const string& strAccount, list<CAccountin
     loop
     {
         // Read next record
-        CDataStream ssKey;
+        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
         if (fFlags == DB_SET_RANGE)
             ssKey << boost::make_tuple(string("acentry"), (fAllAccounts? string("") : strAccount), uint64(0));
-        CDataStream ssValue;
+        CDataStream ssValue(SER_DISK, CLIENT_VERSION);
         int ret = ReadAtCursor(pcursor, ssKey, ssValue, fFlags);
         fFlags = DB_NEXT;
         if (ret == DB_NOTFOUND)
@@ -135,8 +135,8 @@ int CWalletDB::LoadWallet(CWallet* pwallet)
         loop
         {
             // Read next record
-            CDataStream ssKey;
-            CDataStream ssValue;
+            CDataStream ssKey(SER_DISK, CLIENT_VERSION);
+            CDataStream ssValue(SER_DISK, CLIENT_VERSION);
             int ret = ReadAtCursor(pcursor, ssKey, ssValue);
             if (ret == DB_NOTFOUND)
                 break;